With the recent, remarkable development of information technology which has given rise to a trend for information devices that are lighter, thinner and smaller, transparent resins have been used as optical materials in various applications. Typical examples of the transparent resins are poly(methylmethacrylate) resins (PMMA) and polycarbonate resins. The PMMA and polycarbonate, though excellent in transparency, have low glass transition temperature and insufficient heat resistance, and thus are difficult to use in applications requiring high heat resistance. On the other hand, with technology advancement, the applications of engineering plastics have become wider, and polymers excellent in heat resistance, mechanical strength and transparency are demanded.
As a polymer excellent in heat resistance, mechanical strength and transparency, aromatic polyethers obtained by reacting 9,9-bis(4-hydroxyphenyl)fluorene and 2,6-dihalogented benzonitrile are proposed (Patent Literatures 1 and 2).